Thank you all for your highly entertaining discussion which no doubt
will be reprinted the Annals of Scatology (or should that be Anals?).

The problem with separate plumbing for the 2 wells is it would require
500' of trenching, so I view that as a solution of last resort.

The reason to try sterilizing the water, even though the bacterial
testing came up negative, is that there is such a thing as fastidious
bacteria that are not easily detected or cultured.

I do not believe this problem is "nerves" because this was never a high
stress situation, and I certainly did not expect this problem to occur
when I first hooked up the well.

I have repeated the experiment of drinking the water from this well
several times and the irritation is definitely correlated with that.

After the chlorine shock, I ran the well pump for several hours just
flushing the output onto the ground, so I doubt the problem is residual
chlorine or pump oil.

The substances found in the water were calcium, magnesium, zinc, and a
trace of copper, all of which are in my multivitamin supplement in
greater qunatities, sodium, and chloride, nitrate and sulfate at no
more than around 10% of their maximum allowable levels. It seems
unlikely, but I suppose it is possible the nitrate or sulfate could be
irritants. The other possiblity would be some chemical species not
tested for.